It is well-known that there are numerous training aids available to help golfers attempt to improve their golfing game. Some golfers may use simple sticks in order to improve. At a most basic level, many golfers will use one or more sticks to help with the alignment of their swing when hitting the ball. The stick(s) may be placed pointing to the hole to help align the swing relative to the hole, or may be placed in some other position to indicate proper foot position, proper club orientation, proper ration, etc.
Attempts have been made to provide improved training aids which add additional features above sticks alone. For example, U.S. patent application Ser. No. 12/477,752 to Kimball shows a golf swing training device in which a stick 14 is attached to an end piece 18 with a hinge 22 and a locking nut 20. This allows the angle of the stick 14 and the end piece 18 to be adjusted. Thus, when the end piece 18 is stuck in the ground, the stick 14 can be disposed at a variety of angles to help with swing alignment as shown in FIG. 1 of that reference.
A significant improvement was achieved in the Alignment Pro Golf Alignment Rods, an exploded view of which is shown in FIG. 2. Rather than the hinge 36 having to be loosened and retightened each time the user decided to change the orientation of the stick 30 relative to the end piece 34, the Alignment Pro Golf Rods allowed a continuous frictional adjustment in the hinge 36. This was accomplished by a housing 40 attached to the stick and a housing 44 attached to the end piece. Each housing 40, 44 includes a stationary washer 48 with a hole for receiving a pair of mating screws 50, 54. A floating washer 58 is disposed between the other two washers 48. By tightening the mating screws 50, 54, the washers 48 in the housings 40, 44 are brought into frictional contact with the floating washer 58. The tighter the mating screws 50, 54 are applied, the more resistance the hinge 36 provides to movement. Thus, a user can adjust the hinge 36 without the use of tools and at any angle desired between the stick 30 and the end piece 34. Additionally, the Alignment Pro Golf Alignment Rods included a second hinge (not shown) and a second end piece (not shown) at the opposing end of the stick 30.
The use of two self-supporting hinges which can be adjusted without the use of tools and without the need to use (and possibly lose) a wing nut or other locking mechanism—combined with the use of two hinges—makes the Alignment Pro Golf Alignment Rods much more versatile to use. For example, a user may bend both hinged ends down, and insert both ends in the golf turf. This causes the stick to form a table-like shape (with two legs). The golfer can then align their toes with the length of the stick, and pass the head of a putting club under the upper bar of the training device. By watching the movement of the club head relative to the steady plane of the training device, a golfer can determine how close they are to moving the putter to an ideal straight line, or determine whether they are curving or turning their stroke. Because both ends pieces are anchored in the ground, the stick also provides more firm resistance to the club if the user fails to follow the proper movement along the stick.
Alternately, just one end of the training aid can be placed in the ground, and the second end may be angled to point at the golfer's chest. This visual indicator helps a golfer align their chest and head with the ball, and shows a golfer if they are bobbing their head during the swing, and if he is maintaining the proper distance from the ball throughout the stroke.
Alternately, just one end of the training aid may be inserted in the ground, but the remainder of the stick may be suspended in parallel with the ground (e.g. an “L” shape, with the short end inserted in the ground.) This has the advantage of allowing a golfer to pass his or her club under the suspended rail for the full length of a putt. In an ideally straight stroke, the ball would travel directly under the rail for the entire distance of the putt. A golfer can easily see if his putting stroke has any breaks or unevenness because the ball or club may move out of alignment with the rail.
A large number of other golf stances can also be improved by use of a hinged stick. However, the hinge of such a training aid is subject to widely-varying and stressful operating conditions.
For example, the hinge of a golf training aid must be stiff enough to support the entire weight of the stick at any angle, without allowing the stick to slump or give way if accidentally bumped, even in wet conditions. That is to say, the hinge must have sufficient torque. Conversely, the hinge must move easily enough so that the training aid is convenient for use by teenage and women golfers. That is, the hinge torque must not be too great for certain users.
The hinge must be resistant to wear over time, even after a many bending and flexing events, because a user may bend or adjust the ends of the training aid dozens or hundreds of times over the course of just one training session. The hinge must be impervious to moisture, as well as hot and cold conditions, and should function equally well in all environments in which a golfer is likely to use it. The hinge must also be able to undergo long periods of storage (e.g. during the winter) without either growing too stiff to use effectively, or too loose to support the weight of the stick at any angle (i.e., the hinge should have a stable torque force under many conditions.)
In addition, the hinge should also be both low profile and resistant to crushing or other damage. This is because the golf training aid may be repeatedly straightened and jammed into a golf bag, where it may rattle between golf clubs. A high-profile hinge (one which significantly sticks out from the body of the training aid) may become caught or snagged on the lining of the golf bag or golf clubs, damaging the bag or the training aid, or both. Because the golf training aid may be jostled between heavier golf clubs as the bag is carried, the hinge should be resistant to damage.
While the Alignment Pro Golf Alignment Rods are a significant improvement over the cited art, the force necessary to hold the stationary washers 48 in sufficient frictional engagement with the floating washer 58 can be substantial. In an attempt to provide sufficient force that the hinge is self-retaining (i.e. will hold itself at the orientation set by the user) it is not uncommon for the mating screws or their engagement with the housing to break under the stress. Additionally, the floating washer 58 and the stationary washers 48 eventually wear and the hinge must either be retightened or replaced.
Accordingly, there is a need in the art for innovative hinges for golf training aids, and methods of manufacturing hinges suited to use for golf training aids. It is an advantage if the hinge is resistant to degradation as a result of long storage in conditions in heat or cold, even if the hinge is jammed into a golf bag. It is a further advantage if a hinge supports the full weight of the golf training aid at any angle, but is easy enough to bend so that children can use the device. Additionally, it is an advantage if the hinge can be bent and straightened a very large number of times without losing tension. It is also an advantage if the hinge is mostly enclosed, so that grass or debris does not become caught in the joint.